import type { ElForm, ElFormItem } from 'element-plus'
import type Form from '../Form.vue'
import type { FormExpose } from '../formExpose'
import type { FormProps, FormSchema, FormSetProps } from '../types'
import { nextTick, ref, unref } from 'vue'

export function useForm() {
  // From实例
  const formRef = ref<typeof Form & FormExpose>()

  // ElForm实例
  const elFormRef = ref<InstanceType<typeof ElForm>>()

  /**
   * @param ref Form实例
   * @param elRef ElForm实例
   */
  const register = (
    ref: typeof Form & FormExpose,
    elRef: InstanceType<typeof ElForm>,
  ) => {
    formRef.value = ref
    elFormRef.value = elRef
  }

  const getForm = async () => {
    await nextTick()
    const form = unref(formRef)
    if (!form) {
      console.error(
        'The form is not registered. Please use the register method to register',
      )
    }
    return form
  }

  // 一些内置的方法
  const methods = {
    /**
     * 设置form组件的props
     * @param props form组件的props
     */
    setProps: async (props: FormProps = {}) => {
      const form = await getForm()
      form?.setProps(props)
      if (props.model)
        form?.setValues(props.model)
    },

    /**
     * 设置form的值
     * @param data 需要设置的数据
     */
    setValues: async (data: Record<string, any>) => {
      const form = await getForm()
      form?.setValues(data)
    },

    /**
     * 设置schema
     * @param schemaProps 需要设置的schemaProps
     */
    setSchema: async (schemaProps: FormSetProps[]) => {
      const form = await getForm()
      form?.setSchema(schemaProps)
    },

    /**
     * 新增schema
     * @param formSchema 需要新增数据
     * @param index 在哪里新增
     */
    addSchema: async (formSchema: FormSchema, index?: number) => {
      const form = await getForm()
      form?.addSchema(formSchema, index)
    },

    /**
     * 删除schema
     * @param field 删除哪个数据
     */
    delSchema: async (field: string) => {
      const form = await getForm()
      form?.delSchema(field)
    },

    /**
     * 获取表单数据
     * @returns form data
     */
    getFormData: async <T = Record<string, any>>(): Promise<T> => {
      const form = await getForm()
      return form?.formModel as T
    },

    /**
     * 获取表单组件的实例
     * @param field 表单项唯一标识
     * @returns component instance
     */
    getComponentExpose: async <T = any>(field: string) => {
      const form = await getForm()
      return form?.getComponentExpose(field) as T
    },

    /**
     * 获取formItem组件的实例
     * @param field 表单项唯一标识
     * @returns formItem instance
     */
    getFormItemExpose: async (field: string) => {
      const form = await getForm()
      return form?.getFormItemExpose(field) as InstanceType<typeof ElFormItem>
    },

    /**
     * 获取ElForm组件的实例
     * @returns ElForm instance
     */
    getElFormExpose: async () => {
      await getForm()
      return unref(elFormRef)
    },

    getFormExpose: async () => {
      await getForm()
      return unref(formRef)
    },
  }

  return {
    formRegister: register,
    formMethods: methods,
  }
}
